Step-by-step explanation:
[tex] {b}^{2} - 12a[/tex]
where
[tex]a = \frac{1}{4} \\ \\ b = 8[/tex]
[tex] {8}^{2} - 12 \times \frac{1}{4} \\ \\ 64 - 3 \times 1 = 64 - 3 = 61[/tex]